Lesson 2: Telescopes And Galaxies Flashcards
(20 cards)
What do we use telescopes for?
To see things that we cannot see with the unaided eye.
Telescopes are placed in location depending on what?
EM radiation
Some type of telescopes:
Optical telescope
Radio telescope
X-ray telescope
Atmospheric cherenkov telescope
What does optical telescopes collect?
Visible light
What do radiotelescope collect?
Radio waves
What does x-ray telescope collect?
X-rays
Atmospheric cherenkov telescope collect what?
Gamma rays
What is a galaxy?
A gravitational bound system of stars, stellar remnants, interstellar gas, dust, and dark matter
What’s the number of observable galaxies in the universe?
Estimated to be between 2 trillion
What is the galaxy we live in?
Milky Way
Every star you see in the sky is within the Milky Way, true or false?
True
Three types of galaxies:
Spiral
Elliptical
Irregular
Galaxies are classified by what?
By shape, no two galaxies are the same.
Spiral galaxies
Flat discs with slightly thicker centres. When viewed face on they have spiral arms which can be tightly wound or open more.
Elliptical galaxies
Range from nearly spherical to lens shaped. Their stars are concentrated in the centre and they have no spiral arms.
Irregular galaxies
Smaller and fainter than spiral and elliptical galaxies, and their stars are spread unevenly.
The Milky Way is spiral shaped galaxy that is how old?
100,000 light years
What is the nearest galaxy to the Milky Way?
Andromeda galaxy
What is galaxy clusters?
A structure that consists of anywhere from hundreds to thousands of stars bound together by gravity. Known to be the biggest gravitational bound structure in the universe.
What is the Milky Way cluster group called?
Local group
